Apparatus for delivering mold charges from glass-furnaces



S. DAVIDSON AND A. L. SCHRAM. APPARATUS FOR DELIVERING MOLD CHARGES FROM GLASS FURNACES.

APPLICATION FILED JULY 21,1917. 1,338,214. Patented Apr. 27, 1920 l/WEfl/TOHS 50077 Davidson A/exarvaer- L, Sch/am JTTORNEY s. mvznsow AND A. LWSCHRAM;

APPARATUS FOR DELZVERING MOLD CHARGES FROM GLASS FURNACES. APPucAnom FILEDJULY 21.1917.

1 ,338,2 1 4h. Patente Apr 27, 1920.

2 SHEEiS-SHEEl 2.

ATTORNEY SCOTT DAVIDSON AND. ALEXANDER L. SCHRAM, OF HILLSBOIRO, ILLINOIS, ASSIGNOBS UNITED STATES PATENT OFFICE.

TO'SCHRAM GLASS MANUFACTURING COMPANY, OF ST. LOUIS, MISSOURI, A CORPO- BATTON OF MISSOURI.

KEPABATUS FOB DELIVERING MOLD CHARGES FROM GLASS-FUR-NACES.

Specification of Letters Patent.

Patented Apr. 27, it??? Application filed J'ply 23., 1911. Serial No. 182,046.

To all whom it may concern:

Be itknown that we, Sco'r'r DAVIDSON and ALEXANDER L. SCHRAM, citizens of the -United States, residing,- respectively, at

Hillsboro, in the county of Montgomery and State at Illinois, have invented certain new and useful Improved Apparatus for Delivering Mold Charges from Glass-Fun naces, of which the following is a specification, reference being had therein to the' accompanying drawing.

Our invention relates to an improved apparatus for delivering mold charges from glass furnaces, and has forits object to provide an apparatus whereby a series of. single charges of molten glass for a mold --are successively separated from the molten mass contained in the-furnace, and permitted to drop into the mold by gravity.

In attaining this ultimate result we have" also secured the end of maintaining the temperature of the charge, avoiding the chilling of the depending end of the charge (and consequent discoloration of the finished product) by'the means hereinafter described.

As is well known in the art, the high temperature of the molten mass n the glassfurnace must be maintained as nearly as possible in the segregated charge with.

' sity to be used, after the stream is cut, to

retard and hold the oil-coming portion of the stream above the point of severance. This cutting-meansv will inevitably chill the molten glass contacting with it and so result in a defective product. The same result occurs from exposure of the molten charge to the atmosphere, or contact of said molten charge with any gas or solid whose temperature is lower than that of .he mass in the furnace. It is the problem of. averting chilling which our invention solves, by the expedient of delivering the glass from the furnace to the mold by gravity alone, in individual mold-charges or gobs. These gobs depend from the main mass in the furnace when the mold is charged, being connected to the main'mass by a more or less attenuated string of the molten material. The string being severed, the portion above the point of severance is returned upwardly to a point in the discharge-orifice above the outer month thereof, so that the temperature of the lowest part of the next moldcharge is restored to (approximately) the temperature of the furnace contents, by being made a contiguous part thereof. The chilling of the charge at the point of severance is avoided by having the molten glass above the knife immediately drawn upward. and out of con tact with the upper surface of the shears or other cutting instrument, so that at no Figure 1 is a side elevation of an apparatus embodying our invention, the glass furnace and mold being shown,--the former partly, the latter wholly,-in section.

Fig. '2 is a top plan view of'the shears,

illustrating their positioning in relation to the mold.

. Figs. 3, 4:, 5 and 6 illustrate diagrammatically the sequence of the positions of the plunger or valve and the formation of the *gob or mold-charge in the operation of delivering the charge to the mold.

As shown in the drawings the molten mass of material 10 to be fed to the molds 11 is contained in the furnace 12. The furnace-bed 13 isapertured to receive the bushing '14 through which the orifice 15 extends. The orifice has an inner mouth 16 and a lower mouth 17, the inner mouth 16 being closed, when the apparatus is at The shears 21 are mounted on a standard 24 and operated by a foot-lever 25 and its mold-charge, the shears 21 are actuated connections (the rod 26, bell-crank lever 27, oscillating disk 28, and links 29 and 30) as shown in Figs. 1 and 2. s

The mold 11 is carried on the table 31 to which the standard 2% is secured, the shearsand mold-carrying apparatus being movable into and out of position with reference to the furnace 12.

The plunger 19 is mounted through the aperture 32 in the furnace-top 33; and is operated by the hand-hold 34: through the chain 35 and lever 36, which lever 36 is fulcrurned at 37 in the standard F rorn the foregoing description of our apparatus, its mode of operation will be readily understood.-

When the apparatus is at rest the glassmass 10 is quiescent in the interior oi the furnace 12, the orifice 15 being closed by the plunger 19. A mold 11 being; placed in position to receive a charge, the plunger 19 is elevated, permitting the emission of a charge of molten glass through the orifice 15. W hen the emission is sufficient to constitute a toll sever the mold-charge from the coliunn 23 of molten glass, which is conta' led in t is orifice '15 and whose projecting tip hangs, when severed, slightly below the orifice mouth 17 (as in Fig. 4:).

That column 23, severed at its top from the furnace-mass 10 by the plunger 19, it the I plunger 19 remains closed for more than a minute space of time, will attenuate and fall from the orifice 15. But in the practice of our invention continuous operation is contemplated; the plunger 19 is never at rest long enough (when the apparatus is in operation) to permit the column 23 to drop downward. lractically, as soon as the shears 21 have madethe out, the plunger 19 starts its 111 ard iuoveniei it pulls with it tl a cclunni 2o, carrying upward. in the orifice 15 to become conti 'ucus with, an integral part of. and-heated. by the furnace mass 10 (as in i 1 vi hat causes the column to follow the upward move ment of the plunger 19 may be subject to scientific explanation hereafter, but the operation of the apparatus is positively as described, and the result is to elevate the lower extremity of the colzunn so far in the ori fice 15 that whatever chill was present at the instant of severance is overcome, and its temperature again becomes that which it originally had before being segregated from the turnaceunass 10,

The operation of the mechanism of our .invention in actual practice being above described we have found that the best results are attained by the use ol" 2: plunger having a concaved lower face. llut whether the elevation of the cut upper end of the charge through the orifice results a from adhesioi'z of contents ot the orifice to 1 and in so doing lower oi the plunger, or whether the cavity on the lower end oi the plunger forms and contains a vacuum whereby the contents of the orifice is returned upwardly,-the plunger operating as a suction valve,-we have been unable to determine by experinien The actual operation of the mechanism demonstrates that the action of the plunger in its upward movement is like that of a piston and has the eliiect of drawing up the contents of the orifice, merging said contents with the molten mass content of the furnace, and practically restoring the temperature ofthe orifice contents to that of the in the interior of the turnac with which the column 23 has thoroughly commingled, and or which furnace-contents said column 23 has again become a part, by the time the down-stroke of the plunger 19 has begun; and the discharge or a new moldcharge is effected by gravit alone. The same result may be accomplis ed by the use or practice we have found the upward move ment of glass in the orifice to respond more certainly to the action of a plunger having a cupped concentric cavity 20 in its lower face, as herein illustrated and described.

The amount of the discharge "from the furnace will be regulated by the movement I of the plunger.

We are aware that it has heretofore been attempted to provide a glass furnace with a cylindrical cavity in its bottom to receive a charge of molten glass, and to force said charge from said cylindrical cavity by a piston operating therein, and we disclaim such construction; our invention employing an apparatus in which the lower face of the plunge: in iclosed position contacts with the furnace l-OttOln, and does not so contact until the,niold-charge is emitted "from the furnace; said plunger when moved upwardly drawing with it the superfluous molten glass lelt above the severance effected by a shears operating below the outer mouth of the orifice through which the mold charge is emitted.

W e also disclaim the use of a plunger con taining a cavity to which air or steam are admitted to aid in expelling a charge of from a glass furnace, the apparatus and method of our invention contemplating only the use of gravity aided by the pressure of: the plunger in the emission oi the mold-cluirge.

Having thus described our invention, what we claim as new, and desire to have secured to us by the grant of Letters Patent, is

1. An apparatus for delivering mold charges loom glass furnaces, comprising a fcc capable of containing a body of tool-ten and provided with a discharge rate plunger projecting into orifice, said plunge' con-cavity, projecting into said teasers flow by the action of gravity, an imperfesaid furnace and adapted to completely close the upper end of said orifice, the peripheral portion of the lower face of the plunger, being flat and adapted to :torin a close joint with the upper end of the 'wall surrounding the discharge adapted on its down; ward stroke to assist the action ot gravity in the flow of glass through the orifice, and on its upper stroke to retard said How.

2. An apparatus for delivering mold charges from glass furnaces, comprising a furnace capable of containing; a body of molten glass, and provided with a discharge orifice through which molten glass may flow by the action of gravity, an impert'orate j'ilunger provided on its lower end with a furnace and adapted to completely close the upper end of said orifice, the peripheral portion oi the lower face of the plunger being flat and adapted to form a close joint with the upper end of the wall surrounding the discharge orifice, said plunger adapted on its downward stroke to assist the action of gravity in the flow of glass through the orifice and on its upper stroke to retard said flow.

3. An apparatus for charges from glass furnaces, comprising a furnace capable of containing a body of molten glass and provided with adiseharge orifice through which molten glass may flow by the action of gravity, glass severing means located'below the orifice, an imperferate plunger projecting into said furnace and adapted to completely close the upper end of said orifice and to form a close joint with the walls surrounding the orifice, said plunger acting on its upward stroke to retard the flow of glass within the orifice and to replace the severed end of the stream of glass in a position to be heated by the n1ol.-

ten glass contained within the furnace.

In testiu'iony" whereof we hereunto aflix our signatures.

St/QTY Di-U'IDSON. ALEXANDER L. SGI-HLUS'L delivering mold I 

